Stevens, R. (2002). Marketing planning guide.
Lua i Stíl Chicago (17ú heag.)Stevens, Robert. Marketing Planning Guide. Mumbai, 2002.
Lua MLA (9ú heag.)Stevens, Robert. Marketing Planning Guide. 2002.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.